Method and apparatus for controlling an electro-hydraulic differential steering system
First Claim
1. An apparatus for controlling an electro-hydraulic differential steering system of a work machine, comprising:
- a first processing device operable to receive a first signal indicative of a desired steering path, a second signal indicative of a ground speed, a third signal indicative of an engine speed, and a fourth signal indicative of a gage, the first processing device operable to transmit a fifth signal as a function of the first, second, third, and fourth signals, the fifth signal being indicative of a desired pump displacement of the steering system;
a second processing device operable to receive a sixth signal indicative of a motor speed of the steering system, and to receive the third signal, the second processing device operable to transmit a seventh signal as a function of the third and sixth signals, the seventh signal being indicative of an actual pump displacement of the steering system;
a proportional and integral controller coupled with the first processing device to receive the fifth signal and coupled with the second processing device to receive the seventh signal, the controller operable to transmit an eighth signal as a function of the fifth and seventh signals, the eighth signal being indicative of an error between the actual pump displacement and the desired pump displacement;
a third processing device coupled with the first processing device to receive the fifth signal and with the controller to receive the eighth signal, the third processing device operable to transmit a ninth signal as a function of the fifth and eighth signals, the ninth signal being indicative of a pump displacement command signal; and
a fourth processing device coupled with the third processing device to receive the ninth signal, the fourth processing device operable to transmit a tenth signal as a function of the ninth signal, the tenth signal operable to control a first portion of the steering system.
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Accused Products
Abstract
A device for controlling an electro-hydraulic differential steering system of a work machine. A first processing device receives a first signal indicative of a desired steering path, a second signal indicative of a ground speed, a third signal indicative of an engine speed, and a fourth signal indicative of a gage. The first processing device transmits a fifth signal as a function of the first, second, third, and fourth signals, the fifth signal being indicative of a desired pump displacement of the steering system. A second processing device receives a sixth signal indicative of a motor speed of the steering system, and the third signal. The second processing device transmits a seventh signal as a function of the third and sixth signals, the seventh signal being indicative of an actual pump displacement of the steering system. A proportional and integral controller is coupled with the first processing device to receive the fifth signal and coupled with the second processing device to receive the seventh signal.
32 Citations
15 Claims
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1. An apparatus for controlling an electro-hydraulic differential steering system of a work machine, comprising:
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a first processing device operable to receive a first signal indicative of a desired steering path, a second signal indicative of a ground speed, a third signal indicative of an engine speed, and a fourth signal indicative of a gage, the first processing device operable to transmit a fifth signal as a function of the first, second, third, and fourth signals, the fifth signal being indicative of a desired pump displacement of the steering system; a second processing device operable to receive a sixth signal indicative of a motor speed of the steering system, and to receive the third signal, the second processing device operable to transmit a seventh signal as a function of the third and sixth signals, the seventh signal being indicative of an actual pump displacement of the steering system; a proportional and integral controller coupled with the first processing device to receive the fifth signal and coupled with the second processing device to receive the seventh signal, the controller operable to transmit an eighth signal as a function of the fifth and seventh signals, the eighth signal being indicative of an error between the actual pump displacement and the desired pump displacement; a third processing device coupled with the first processing device to receive the fifth signal and with the controller to receive the eighth signal, the third processing device operable to transmit a ninth signal as a function of the fifth and eighth signals, the ninth signal being indicative of a pump displacement command signal; and a fourth processing device coupled with the third processing device to receive the ninth signal, the fourth processing device operable to transmit a tenth signal as a function of the ninth signal, the tenth signal operable to control a first portion of the steering system. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 13, 14, 15)
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11. A work machine, comprising:
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a frame; at least two ground engaging traction devices coupled with the frame; a control input device coupled with the frame and operable to transmit a desired steering path signal as a function of an input; a velocity sensor coupled with the frame, the velocity sensor operable to transmit a ground speed signal as a function of a ground speed of the work machine; an engine coupled with the frame, the engine operable to produce a kinetic force; an engine speed sensor coupled with the engine and operable to transmit an engine speed signal as a function of an engine speed; a gage signal generator operable to transmit a gage signal as a function of the gage of the ground engaging traction devices; an electronic controller comprising; a first processing device coupled with the control input device to receive the steering path signal, with the velocity sensor to receive the ground speed signal, with the engine speed sensor to receive the engine speed signal, and with the gage signal generator to receive the gage signal, the first processing device operable to transmit a desired pump displacement signal as a function of the steering path signal, ground speed signal, engine speed signal, and gage signal; a second processing device operable to receive a motor speed signal, and coupled with the engine speed sensor to receive the engine speed signal, the second processing device operable to transmit an actual pump displacement signal as a function of the engine speed signal and the motor speed signal; a proportional and integral controller coupled with the first processing device to receive the desired pump displacement signal and coupled with the second processing device to receive the actual pump displacement signal, the controller operable to transmit an error signal as a function of the desired pump displacement signal and the actual pump displacement signal; a third processing device coupled with the first processing device to receive the desired pump displacement signal and with the proportional and integral controller to receive the error signal, the third processing device operable to transmit a pump displacement command signal as a function of the desired pump displacement signal and the error signal; and a fourth processing device coupled with the third processing device to receive the pump displacement command signal, the fourth processing device operable to transmit a first pump control signal as a function of the first pump displacement command signal; a hydraulic pump coupled with the fourth processing device to receive the first pump control signal, and operable to produce a fluid flow as a function of the first pump control signal; a motor coupled with the hydraulic pump to receive the fluid flow and coupled with at least two of the ground engaging traction devices, the motor operable to increase the velocity of one of the ground engaging traction devices and to decrease the velocity of another of the ground engaging traction devices as a function of the fluid flow; a motor speed sensor coupled with the motor and with the second processing device, the motor speed sensor operable to transmit a motor speed signal to the second processing device as a function of a motor speed of the motor; and a transmission coupled with the engine to receive the kinetic force, and coupled with two of the ground engaging traction devices, the transmission operable to rotate the two ground engaging traction devices at an equal velocity as a function of the kinetic force, the total velocity of each of the two ground engaging traction devices comprising the equal velocity from the transmission plus the differential velocity from the motor.
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12. A method for controlling an electro-hydraulic differential steering system of a work machine, comprising:
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receiving a first signal indicative of a desired steering path; receiving a second signal indicative of a ground speed; receiving a third signal indicative of an engine speed; receiving a fourth signal indicative of a gage; transmitting a fifth signal as a function of the first, the second, the third, and the fourth signals, the fifth signal being indicative of a desired pump displacement of the steering system; receiving a sixth signal indicative of a motor speed of the steering system; transmitting a seventh signal as a function of the sixth signal and the third signal, the seventh signal being indicative of an actual pump displacement of the steering system; determining a ninth signal as a function of the difference between the fifth signal and the seventh signal, the ninth signal being an error signal including a proportional term and an integral term; adding the fifth signal with the ninth signal; transmitting a tenth signal as a function of the sum of the fifth and ninth signals, the tenth signal operable to control a first component of the steering system.
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Specification